Possible off-topic alert, I'm asking this here because msbl-db01.hotmail.com
seems to limit itself to targeting our Listserv engine, and I'm wondering if
other Listmasters see it or know what it is.

Basically, msbl-db01.hotmail.com shows up in the logs every afternoon, at no
fixed time, attempting to *telnet* into our Listserv engine about 18 times.
In writing this I just noticed that it's also generating some 404's on the
web interface at the same time.  It has been doing this for many months at
least, more likely a couple of years, and inquiries about it directed to
various hotmail addresses simply vanish.  I don't recall ever getting anything
out of it from a port scan, and running "msbl-db01" past Google merely shows
it as being on other peoples radar for the last two years.

                                                      -Kary